Light and the brain
Light regulates our hormone production
The nerve centers of the brain, which control our daily rhythm, are stimulated by daylight. At night, we produce the hormone melatonin, causing us to become tired. Normally, the production of melatonin stops with sunrise, but this does not happen in winter, when we get up before the sun rises. Melatonin production rises as soon as light wanes, and peaks between the hours of 12:00 midnight and 2:00 a.m. Research has shown that Melatonin production naturally decreases with passing years. By the age of 60, we produce half of what we did at 20.
We simply don´t get enough sunlight to stop the production of melatonin. That’s why we constantly feel tired in winter mornings. Studies show, that the impact of light slows down the production of the sleeping hormone melatonin but also promotes the production of the mood-controlling hormone serotonin.
A lack of serotonin is one of the most common reasons for depressions.
By treating people with artificial light (in combination with certain light wavelengths) it is possible to regulate hormone production and thus improve moods and the state of mind.